I have a table with static data. For reasons way too long to go into, I need to add a column, and the value of that column will need to be a concatenation of two other existing fields in that same table. It's got something like 225000 rows, so I cannot do it manually. I'm googling and not seeing much that will help on this. I imagine it's a simple T-SQL statement, but am drawing a blank.

Using SQL Server 2005.

To be clear: I am not talking about selecting from the table and doing the concatenating on the fly. I want to add a column.